金屬有機骨架薄膜之氣體分離應用與質傳性質探討

Metal-Organic Framework Membranes for Gas Separations and the Study on Their Mass Transport Properties

甘名揚(Ming-Yang Kan)

指導教授 ： 康敦彥

國立臺灣大學/工學院/化學工程學研究所/博士(2021年)

https://doi.org/10.6342/NTU202101965

摘要

金屬有機骨架(Metal-organic frameworks, MOFs)是一種具備高結晶性的孔洞材料，由於其多樣性、獨特的吸附性質與可調控孔徑尺寸的優點，在薄膜分離領域被認為具有極高的發展潛力，例如薄膜氣體分離與薄膜滲透蒸發。然而，至今金屬有機骨架薄膜應用於氣體分離的技術仍有許多待克服的挑戰，包含薄膜中容易有缺陷產生，以及分子在其孔洞中的輸送機制亦尚未被完全理解。本研究期望藉由自行搭建的薄膜氣體通透設備以量測自製的金屬有機骨架薄膜之氣體通透效能，並且結合分子模擬來釐清其質傳機制。首先，我們搭建了可以分別使用定壓法與定容法量測薄膜氣體通透率的設備。接著，我們製備名為Zn-AIP-AZPY的新穎MOF薄膜，量測其對於氫氣、二氧化碳、甲烷的通透率，並以in situ XRD的技術分析此MOF於吸附氣體時造成的結構形變。將Zn-AIP-AZPY的配位基置換後，可形成另一種名為CPO-8-BPY，結構彈性較低的MOF。我們研究以介電質放電電漿輔助合成CPO-8-BPY薄膜的方法，並透過固態NMR、XPS等多種分析工具釐清電漿對於CPO-8-BPY微結構之影響。我們於實驗中量測CPO-8-BPY薄膜對於氫氣、氮氣、甲烷的通透情形，並輔以分子模擬來釐清其分子擴散機制。

關鍵字

金屬有機骨架 ； 金屬有機骨架薄膜 ； 薄膜氣體分離

並列摘要

Metal-organic frameworks are porous materials with high crystallinity. Due to the high diversity, good adsorption properties, and tunable pore topology, MOFs have been considered as potential candidates for membrane gas separations and pervaporations. However, applying pure MOF membranes in gas separations is still challenging. This is mainly due to the defects eternally forming in the membrane layer, and the molecular transport mechanism in the pore channel remains unclear. In this thesis, we aim to characterize MOF membranes separation performance through a home-made gas permeation equipment. Combined with molecular simulations, we can get insight into the gas diffusion behaviors. We first built a gas permeation system that can run both constant-volume and constant-pressure method for membrane permeation measurements. We then fabricated a pure MOF membrane with an emerging MOF compound, denoted as Zn-AIP-AZPY, and characterizing the gas permeability of H2, CO2, and CH4. The in situ XRD technique was employed to analyze the structure deformation under various gas adsorption. Finally, the pillaring ligand in Zn-AIP-AZPY was replaced to form a less flexible MOF named CPO-8-BPY. We used dielectric barrier discharge on the fabrication of CPO-8-BPY membrane. With comprehensive materials characterization, involving solid-state NMR, XPS, etc., we realized that how the plasma affects the microstructure of CPO-8-BPY. The permeability of H2, N2, and CH4 was identified as well, and the molecular simulations were employed for probing the diffusion properties.

並列關鍵字

metal-organic framework ； metal-organic framework membrane ； gas separation

參考文獻

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